Conventionally, a multi-needle sewing machine has been used which is capable of consecutively sewing embroidery patterns that require the use of a plurality of thread colors. Such multi-needle sewing machine is provided with sewing data and a plurality of sewing needles. The sewing data includes thread color data that specifies a thread color and needle drop point data that specifies a needle drop point position for each stitch. A plurality of sewing needles is respectively attached to needle bars which are each set with a thread of different color.
The multi-needle sewing machine loads the sewing data upon starting a sewing operation. Then a switch is made to the sewing needle set with a thread having a thread color that matches with the loaded thread color data, and sewing operation is executed based on the loaded needle drop point data. Such sewing needle switching is carried out when replacing the thread color to be used for a sewing process. At this point, in case a sewing needle set with a thread that matches with the thread color specified in the thread color data does not exist, the user makes the replacement to the thread having a matching thread color.
A multi-needle sewing machine disclosed in JP-A-6-15072 is provided with a storage medium that stores thread type (thread color) data of the thread set to the sewing needle. The multi-needle sewing machine loads the sewing data upon embroidery sewing. Then, in case the sewing needle set with the thread having the thread color matching the thread color data specified in the sewing data does not exist, sewing operation is stopped to enable the replacement of the thread spool by the user.
Similarly, a sewing machine control device disclosed in JP-A-2004-33538 stops the sewing operation when a sewing needle set with a thread having a thread color matching the thread color data specified in the sewing data does not exist. Then, in the subsequent sewing operation, the sewing needle set with the least frequently used thread color is determined. Then the user is informed of a specific thread spool to be replaced so that highest replacement efficiency can be attained.
The thread replacement described above requires the user to set the sewing needle with the thread in addition to the replacement of the thread spool itself, which is a troublesome work for the user. Performing such operation upon every absence of matching thread color imposes considerable burden on the part of the user.